Furnace and apparatus for heat treating the edges of metallic material



Nov. 10, 1942.

D. H. E. GENTER FURNACE AND APPARATUS FOR HEAT TREATING' THE EDGES OF METALLIC MATERIAL Filed April 8, 1941 Patented Nov. 10, 1942 FURNACE AND APPARATUS Foa nna'r TREATING rm: EDGES or METALLIC m- TERIAL David H. E. Genter, Pittsburgh, Pa.

Application April 8, 1941, Serial No. 387,522

'1 Claims. (01. 263-2) This invention relates to the heat treating of the edges of metallic material and, particularly, to an improved furnace and apparatus for performing such heat treating.-

As is well known to those in the steel industry, when metallic material such as steel is cut by means of an oxy-acetylene flame, the physical properties of that portion of the material alon the cut change and the edge of the material so cut, particularly the material at the surface of the cut, hardens materially, thus renderin this surface and the edge of the material too hard to properly machine. Also, such flamecut edges of the material are susceptible to cracking if these edges are not heat treated after the flame cutting operation. which, of course, is objectionable. Such a result is primarily due to the fact that when the steel is cut, a drastic quenching takes place at the cut surface, due to rapid dissipation of the heat of the flame back into the body of the material. The depth to which such quenching act-ion extends back into the material, of course, varies with the size, condition and composition of the material bein cut and the type of equipment and the manner in which the cutting is done.

Thus, it is desirable and necessary to heat treat the edge of the material after the cutting operation sufllciently to draw back or anneal that portion of the material aiTected by the cutting operation so as to improve the physical properties of the material along the cut edge, whereby either the machinability of i the cut edge will be improved or cracking will be eliminated, or both, as the case may be.

Heretofore, this heat treating of the cut edge I was accomplished by moving an open flame, usually an oxy-acetylene torch, along the edge of the material and apply n sufllcient heat to the cut edge thereof to overcome the above named disadvantages. However, the use of an open flame for such a purpose is not satisfactory, primarily for the reason that it is difllcult to control the heat input thereof, and consequently the amount of heat applied is not uniform. Furthermore, an open flame is too erratic and undependable for the use of heat treating such cut edges on a commercial scale. Therefore, it will be seen that in heat treating such edges, or in flame softening, as it is sometimes called, the problem is one of producing, confining and maintaining a' desired heat efiect at the flame-cut edge and surface.

In the present invention, there is provided broadly a refractory-lined shell or box-like member in the form of a furnace for housing the softening or heat treating flame, which is disposed between the fuel burner and the cut edge of the metallic material to be heat treated, thereby eliminating the above named disadvantages.

Accordingly. it is the general object of my invention to provide an improved furnace and apparatus for heat treating the edges of flamecut material by which the edges of metallic material may be uniformly heated.

It is another object of the invention toprovide an improved furnace and apparatus for heat treating the edges of metallic material which is simple and inexpensive in its construction and, at the same time, one which is efllcient and effective in its use.

Various other objects and advantages of this invention will become more apparent during thecourse of the following specification and will be particularly pointed out in the appended claims. In the accompanying drawing there is shown. for the purpose of illustration, one embodiment which my invention may assume in practice.

In the drawing: Figure 1 is a front perspective view of the improved furnace and apparatus of my invention; Figure 2 is a front elevation of my improved furnace;

Figure 3 is a section taken on line III-411 of Figure 2; and

Figure 4 is a section taken on line rv-rv of Figure 3.

-Referring more particularly to the drawing,

t the improved furnace of my invention comprises a box-shaped, or preferably a U-shaped body member 2 so as to providea pair of spaced apart outwardly extending portions 3. The body member 2 is preferably made of metal, such as steel and the like, and is preferably lined with refractory brick or some other suitable refractory material. There is arranged pre'ferabhr' in the rear side of the body member 2 preferably a rec'- tangular-shaped port or opening 4 in which there is adapted to be disposed a ribbon burner 5. There is disposed between the outwardly extending portions 2, side walls 6 which are adapted to serve as sidewalls for the body member so as to provide a heating chamber 1 therewithin. The

burner 5 is connected by means of the connection 8 to any suitable source of fuel supply, preferably an oxygen or compressed air and gas supply, through a blowpipe mixer I.

Thereis provided preferably a bracket II for supporting the body member 2 as at II and I2 and the bracket is attached in any suitable manabutting relation with the outer sides of the side walls 6. The burner 5 is then lighted and the fuel supply adjusted so that the proper flame for heat treating and softening the edge of the material is delivered through the port 4 into the heating chamber 1 between the outwardly extending portions 3 to the cut edge of the plate or material. The mechanism for moving the furnace, such as the cutting machine III, is then set in operation so that the furnace will be moved along the flame-cut edge so as to expose the same to the action of heat'in the heating chamber 1. It will be seen that the outwardly extending portions 3 act to guide the furnace along the edge of the plate or material and that the side walls 6 space the edge of the material from the burner 5 so that the proper amount of heat is applied to the edge of the material. 'Thus,'in effect, there is provided a traveling furnace which, as it moves along, exposes the edge of the material to the action of the heattherein, thereby softening the same. While it is preferable that the furnace be moved along the edge of the material with the material remaining-stationary, it will be understood that the material may be moved with the furnace remaining stationary if it is so desired. That is, any

.suitable arrangement may be provided whereby the furnace and the edge of the material move relative to each other or whereby no movement is necessary by virtue of equivalent length of furnace relative to size of material.

As a result of my invention, it will be seen .thatthere is provided a means for softening the cut surfaces of metallic material in which the heat input can be easily and conveniently controlled and in which the hardness in the heataifected zone at and near the surface of the cut can be reduced to the desired degree. It will also be seen that with the ues of the furnace of the present invention, considerable fuel saving is attained, due to the fact that the heating flame is enclosed and heat loss to the surrounding atmosphere .is decreased and practically eliminated thereby, Also, with the use of such a furnace, the heat absorbed by the walls thereof is radiated to the edge of the plate or material being heat treated or softened, which is a decided advantage.

It will also be seen that with the use of the present furnace, a softer and yet a more soaking or penetrating heat is provided so as to properly I claim:

1. A furnace of the class described comprising a movably arranged body member, means arranged with said body member for receiving the edge of the material to be heat treated, said body member having a port arranged in one side thereof, a fuel burner arranged .opposite said port for delivering a flame therethrough to the edge of said material, and means carried by said body member against which the edge of the material is adapted to abut for spacing the same from said burner.

2. A furnace of the class described comprising a substantially U-shaped movably arranged body member so as to provide a pair of spaced apart outwardly extending portions with the edge of the material to be heat treated adapted to be disposed between said 'outwardlyextending portions, said body member having a port arranged in the side thereof, a fuel burner arranged opposite said port for delivering a flame therethrough between said outwardly extending portions to the edge of the material to heat treat the same, and means carried by said body member against which the edge of the material is adapted to abut for spacing the same from said burner.

3. A furnace of the class described for heat treating the edges of metallic material comprising a movably arranged body member having a heating chamber arranged therein, means for delivering heat into said heating chamber, said body member having an opening arranged in one side thereof communicating with said heating chamber for receiving the edge of the material to be heat treated with said body member and the edge of the material adapted to be moved relative to each other, and means arranged with said body member for spacing and guiding the same along the edge of the material during their movement'relative to each other.

4. Apparatus of the class described including, in combination, a movable supporting means, a fuel burner mounted on said supporting means for delivering a flame to the edge of the material to be heat treated, means carried by said supporting means and arranged between the burner and the edge of said material for housing said flame, and means arranged with said last mentioned means against which the edge of the material is adapted to abut for spacing the same from said burner.

5. Apparatus of the class described including, in combination, a fuel burner for delivering a flame to the edge of the material to be heat treated, a body member arranged between said burner and the edge of said material for housing said flame and for spacing the edge of the material from said burner, and movable means for carrying said housing member together with said burner, said movable means adapted to move said housing together with said burner along the edge of said material.

6. Apparatus of the class described including,

in combination, a fuel burner for delivering a flame to the edge of the material to be heat treated, a substantially U-shaped body member arranged between said burner and the edge of said material for housing said flame so as to provide a pair'of outwardly extending portions with the edge of the material to be heat treated adapted to be disposed between said outwardly extending portions, said body member having a port arranged in the side thereof through which the flame is adapted to pass between said outwardly extending portions to the edge of said material, means arranged between said outward- 1y extending portions against which the edge of the material is adapted to abut for spacing the same from said burner, and means for moving the said burner together with said body member relative to the edge of said materiaL.

7. Apparatus of the class described forheat treating the edges-of metallic material includtending portions arranged on one side thereof,.

said body member. having an opening arranged in the side thereof between said outwardly extending portions with the edge of the material to be heat treated adapted to be disposed opposite said opening against the side of said body member between said outwardly extending portions,

said body member having a port arranged in the side thereof directly opposite said opening in the opposed side of the body member, a fuel burner arranged opposite said port for delivering a flame therethrough and through the opening to the edge of-said material, and movable means DAVID H. E. Gama. 

